Finger guard for power distribution panel

ABSTRACT

A finger guard for an electrical circuit breaker includes a rear plate with an opening, a guard portion extending from the plate adjacent the opening, and a removable portion, or knock-out, positioned within the opening. A further finger guard for an electrical circuit breaker includes a rear plate with an opening, a guard portion extending from the plate adjacent the opening, and opposing ramped finger grips on the outer walls of the guard portion. A further finger guard for an electrical circuit breaker includes a rear plate with an opening, and a guard portion extending from the plate adjacent the opening, the plate further including a designation holder. An electrical power distribution system with a chassis having an electrical circuit including a mount for an electrical circuit breaker and an opening providing access to the mount, includes a finger guard mounted across the opening. A method of removing a finger guard from an opening on an electric power distribution chassis, removing a portion covering an opening in the finger guard, mounting the finger guard to an electrical circuit breaker, and inserting the electrical circuit breaker into a circuit breaker mount in an electrical circuit within the chassis.

FIELD OF THE INVENTION

[0001] The present invention relates to power distribution units. Morespecifically, the present invention relates to providing finger guardsfor circuit breakers used with power distribution units.

BACKGROUND OF THE INVENTION

[0002] Power distribution units are used to distribute power supplied bya main electrical source to a variety of devices requiring power. Thepower distribution unit may include an internal power bus that powersone or more circuits. Each of these circuits may include a protectivedevice, such as a fuse or a circuit breaker, which is accessible throughone of the walls or panels of the unit. A power distribution unit mayhave the capacity for more circuits than are required when the unit isinstalled, which provides for future expansion. In such installations,one or more of the circuits may be left open, that is, without havingany protective device.

[0003] The openings through which these omitted protective devices willextend are often covered to prevent unwanted or accidental contact withthe power bus within the unit. This may be done with a flat plate orblank cover secured over the opening. When a protective device isinserted into the opening to provide an additional power circuit, thisblank is then removed and discarded. A mounting plate may then beattached to the protective device and the device inserted into the powerdistribution unit. When a switched circuit breaker is the protectivedevice installed, the mounting plate may incorporate a finger guardstructure to protect the switch from accidental contact opening thecircuit and interrupting power in the circuit.

[0004] Several concerns arise in the area of finger guards, includingease of use and reliability. Providing separate mounting plates andblank covers can be difficult to coordinate and manage, especially whenthe circuit protective devices are added later. Further developments infinger guards are desired.

SUMMARY OF THE INVENTION

[0005] The present invention relates to a finger guard for an electricalcircuit breaker, the finger guard including a rear plate with anopening, a guard portion extending from the plate adjacent the opening,and a removable portion, or knock-out, positioned within the opening.

[0006] The present invention further relates to a finger guard for anelectrical circuit breaker, the finger guard including a rear plate withan opening, a guard portion extending from the plate adjacent theopening, and opposing ramped finger grips on the outer walls of theguard portion.

[0007] The present invention also relates to a finger guard for anelectrical circuit breaker, the finger guard including a rear plate withan opening, a guard portion extending from the plate adjacent theopening, and the plate further including a designation holder.

[0008] The present invention relates as well to an electrical powerdistribution system with a chassis having an electrical circuitincluding a mount for an electrical circuit breaker and an openingproviding access to the mount, a finger guard mounted across theopening, the finger guard including an opening covered by a removableportion.

[0009] The present invention also relates to an electrical powerdistribution system with a chassis having an electrical circuitincluding a mount for an electrical circuit breaker and an openingproviding access to the mount, a finger guard mounted across theopening, the finger guard including opposing ramped finger grips on theouter walls of the guard portion.

[0010] The present invention further relates to an electrical powerdistribution system with a chassis having an electrical circuitincluding a mount for an electrical circuit breaker and an openingproviding access to the mount, a finger guard mounted across theopening, the finger guard including a designation holder.

[0011] The present invention relates as well to a method of removing afinger guard from an opening on an electric power distribution chassis,removing a portion covering an opening in the finger guard, mounting thefinger guard to an electrical circuit breaker, and inserting theelectrical circuit breaker into a circuit breaker mount in an electricalcircuit within the chassis.

BRIEF DESCRIPTION OF THE DRAWINGS

[0012] The accompanying drawings, which are incorporated in andconstitute a part of the specification, illustrate several aspects ofthe invention and together with the description, serve to explain theprinciples of the invention. A brief description of the drawings is asfollows:

[0013]FIG. 1 is a front perspective view of a portion of a powerdistribution unit according to the present invention.

[0014]FIG. 2 is a front view of the power distribution unit of FIG. 1.

[0015]FIG. 3 is a side view of the power distribution unit of FIG. 1.

[0016]FIG. 4 is a bottom view of the power distribution unit of FIG. 1.

[0017]FIG. 5 is a side view of a finger guard according to the presentinvention mounted to a switchable circuit breaker and a schematicelectrical circuit including a circuit breaker mount for the powerdistribution unit of FIG. 1.

[0018]FIG. 6 is a front perspective view of a finger guard according tothe present invention.

[0019]FIG. 7 is a front view of the finger guard of FIG. 6.

[0020]FIG. 8 is a side view of the finger guard of FIG. 6.

[0021]FIG. 9 is a rear view of the finger guard of FIG. 6.

[0022]FIG. 10 is a bottom view of the finger guard of FIG. 6.

DETAILED DESCRIPTION

[0023] Reference will now be made in detail to exemplary aspects of thepresent invention that are illustrated in the accompanying drawings.Wherever possible, the same reference numbers will be used throughoutthe drawings to refer to the same or like parts.

[0024]FIG. 1 shows a portion of a power distribution panel 10 for use ina telecommunications installation, such as a rack, to provide power toother devices within the same installation. Panel 10 includes protectivedevices in the form of circuit breakers and fuses. Typically on the rearof panel 10 is a power input connection 98 where a power supply feed isconnected. As shown in FIG. 5, an internal bus 100 distributes thecurrent provided through power input connection 98 into a series ofseparate distribution circuits 102. Each distribution circuit 102 iselectrically connected with a power output connection 112 by a lead 104.Power output connection 112 is also on the rear of panel 10, andprovides power to a device mounted elsewhere in the telecommunicationsinstallation. Distribution circuits 102 require a protective device suchas circuit breaker 30 be mounted in the distribution circuit to completethe electrical path and to provide over-current protection for thedistribution circuit.

[0025] Referring now to FIGS. 1 through 4, power distribution panel 10includes a front face 12, a side 14, a top 16 and a bottom 18, alongwith a rear face and an opposing side which are not shown, forming anenclosure for the power bus housed by panel 10. Finger guards 20 aremounted in an access opening 22 in front face 12. Behind each of sixfinger guards 20 are mounts 110 to mount the protective devicescompleting and providing over-current protection for each of sixinternal distribution circuits 102. Power distribution units may includemore or less than the six circuits 102 shown. Also located on front face12 are power indicator lamp 24 and electrical fuse array 26, providingadditional over-current protection to electrical circuits within powerdistribution panel 10.

[0026]FIG. 5 shows finger guard 20 mounted to the front of a protectivedevice, in this case a switched circuit breaker 30. Also shown is mount110 of distribution circuit 102 for receiving such a protective device.A pair of mounting studs 32, located at the rear of circuit breaker 30,interface with the stud receivers 106 which are part of mount 110.Insertion of mounting studs 32 in stud receivers 106 and placing switch33 of switched circuit breaker 30 into a closed position will completethe electrical path for each distribution circuit 102. Also located tothe rear of circuit breaker 30, between mounting studs 32, are alarmleads 34. Alarm leads 34 are received by alarm interface 108 of mount110 to provide a connection with alarm circuits 114 within powerdistribution panel 10. Alarm circuits 114 will initiate failure alarmswhen the current flowing through circuit breaker 30 is disrupted. Alsoshown in FIG. 5 are screws 21, which are discussed further below.

[0027] Referring now to FIG. 6, finger guard 20 includes a front face44, a rear face 46, side guards 36, a top wall 38 and a bottom wall 40cooperating to define an enclosure 42. A removable portion or knock-out56 closes a portion of the rear of enclosure 42 while the front ofenclosure 42 is open. A portion of the rear of the enclosure is openedby the removal of knock-out 56, forming an opening 57, through which aportion 31 of circuit breaker 30 extends, as shown in FIG. 5. Alsoextending from circuit breaker 30 through opening 57 into enclosure 42is switch 33 for setting circuit breaker 30 into an open or closedposition. The remainder of the rear of enclosure 42 is closed by frontface 44 and rear face 46.

[0028] At the bottom of finger guard 20 is located an indicia holder 48through which is formed opening 61. An indicia cover 52 removably mountsto the front of indicia holder 48. Cover 52 can include indicia or itcan be transparent to visible light for trapping a designation card 50to identify the circuit protected by circuit breaker 30. Cover 52includes opposing edges 114 along the rear which engage lips 116 alongthe top and bottom of indicia holder 48 to securely and removably holdcover 52 to indicia holder 48.

[0029] Located on the distal ends of the outer surfaces of top wall 38and bottom wall 40 are opposing ramped finger grips 54. Ramped fingergrips 54 provide a positive and comfortable surface for grasping andremoving circuit breaker 30 connected to mount 110 inside powerdistribution panel 10, when finger guard 20 is mounted to circuitbreaker 30, as shown in FIG. 5. Ramped finger grips 54 may have ridges55 formed in the ramped surface, as shown in FIG. 8, or may be have somealternative surface treatment to increase friction and improve grip.

[0030] Referring now FIGS. 7 through 10, mounting openings 60 extendfrom front face 44 to rear face 46 of finger guard 20. Mounting openings60 receive removable fasteners such as screws 21 for securing fingerguard 20 to circuit breaker 30. The upper mounting opening 60 is locatedwithin enclosure 42 above knock-out 56. Openings 60 may be located inother positions along finger guard 20.

[0031] Knock-out 56 is joined to finger guard 20 by perforations,webbing or thinned portions 45, such as along the top and bottom ofopening 57. Knock-out 56 is removed from opening 57 by applying force toknock-out 56 from the rear sufficient to break thinned portions 45.Alternatively, notches 41 in knock-out 56 provide openings for theinsertion of a flat-bladed tool such as a screwdriver from the front andapply force to the rear of knock-out 56 using the leverage of thescrewdriver to break thinned portions 45. Finger guard 20 is made frommolded plastic having appropriate physical properties to permit theconnection between finger guard 20 and knock-out 56 to be broken alongthinned portions 45 with the application of reasonable force withoutdamaging the remainder of finger guard 20.

[0032] Along the rear of finger guard 20 is a rear notch 64 in sideguards 36. Rear notch 64 is sized to receive portion 31 of circuitbreaker 30 when finger guard 20 is mounted to circuit breaker 30. Notall circuit breakers include such an extension 31, having instead a flatfront face. In addition, other protective devices may or may not havesuch an extension 31. Finger guard 20 is usable with such otherprotective devices, with or without an extension 31.

[0033] Side guards 36 include an arched portion 66 to provide additionalprotection to switch 33 of switched circuit breaker 30 extending intoenclosure 42. Arched portion 66 is shown coextensive with opening 57 andrear notch 64. Side guards 36 may have alternative shapes, either curvedor straight, provided that side guards 36 extend enough from front face44 to provide the desired protection to the switch 33.

[0034] Power distribution panel 10 may include one or more internaldistribution circuits 102 without a protective device such as circuitbreaker 30 completing the electrical pathway between the power inputterminal 98 and the power output terminal 112. In this case, opening 22in front face 12 proximate the mounts 110 for the protective deviceswill be covered by a finger guard 20, as shown in FIG. 2. Finger guard20 is held to front face 12 by a tab 62 inserted into a slot 68 throughfront face 12 above opening 22. Tab 62 includes a ramped portion 120which extends through slot 68 and engages the rear of front face 12.Opening 61 through indicia holder 48 also accepts a removable fastenersuch as a screw 21 which engages an opening 69 through front face 12below opening 22 to secure finger guard 20 to front face 12. Knock-out56 covers opening 57 and cooperates with front face 44 of finger guard20 when mounted to front face 12 of panel 10 to prevent accidental orunwanted contact with the electrical power components within panel 10.

[0035] To complete a distribution circuit, finger guard 20 is removedfrom front face 12 by removing the removable fastener such as screw 21from opening 69 and opening 61, and withdrawing tab 62 from slot 68.Knock-out 56 is removed from opening 57 by exerting force on the rear ofknock-out 56 and breaking thinned portions 45. Finger guard 20 in thenplaced on the front of a protective device such as circuit breaker 30 sothat portion 31, if present, extends into rear notch 64 and switch 33 ofcircuit breaker 30 extends into enclosure 42. Removable fasteners suchas screws 21 are then inserted through openings 60 to engage appropriateopenings in circuit breaker 30 to mount finger guard 20 to circuitbreaker 30. Circuit breaker 30 with finger guard 20 mounted to it isthen inserted through opening 22 in front face 12 of panel 10 so thatmounting studs 32 engage stud receivers 106 of mount 110 in distributioncircuit 102 and alarm leads 34 are received by alarm interface 108. Asthe circuit breaker is fully inserted into the mount, tab 62 of fingerguard 20 again engages an edge of slot 68 on front face 12 of panel 10and rear face 46 of finger guard 20 rests against front face 12. Aremovable fastener such as screw 21 is then inserted through opening 61to engage opening 69, securing finger guard 20 to front face 12.

[0036] With regard to the foregoing description, it is to be understoodthat changes may be made in detail, especially in matters of theconstruction materials employed and the shape, size and arrangement ofthe parts without the scope of the present invention. It is intendedthat the specification and depicted aspects be considered exemplaryonly, with a true scope and spirit of the invention being indicated bythe broad meaning of the following claims.

What is claimed is as follows:
 1. A finger guard for an electricalcircuit breaker, the finger guard comprising: a body including a frontface and a rear face; an opening formed from the front face to rearface, the opening sized to receive a switch of an electrical circuitbreaker; first and second side guards on the front face extendinggenerally perpendicular to the front face and defining opposing sides ofthe opening; a knock-out positioned within the opening, the knock-outremovably attached to the body and substantially blocking the opening;and at least one fastener opening through the body for mounting to aswitched electrical circuit breaker with the switch of the circuitbreaker extending into the opening.
 2. The finger guard of claim 1,further comprising a top wall and a bottom wall extending from the frontface along a top and bottom of the opening, respectively, the top andbottom walls being generally perpendicular to the side guards andextending from the first side guard to the second side guard, defining asubstantially rectangular bounded area on the front face positionedabout the opening.
 3. The finger guard of claim 2, wherein the top wallincludes an outer surface and a distal edge and the bottom wall includesan outer surface and a distal edge, and a first raised ramped fingergrip is positioned proximate the distal edge of the outer surface of thetop wall and a second raised ramped finger grip is positioned proximatethe distal edge of the outer surface of the bottom wall, the raisedramped finger grips cooperating to define opposing finger holds.
 4. Thefinger guard of claim 2, further comprising a designation holderextending from the front face adjacent to either the top wall or thebottom wall outside the bounded area for receiving indicia.
 5. A fingerguard for an electrical circuit breaker, the finger guard comprising: abody including a front face and a rear face; an opening formed from thefront face to rear face, the opening being approximately rectangular andhaving a top and a bottom, the opening sized to receive a switch of anelectrical circuit breaker; first and second side guards on the frontface extending generally perpendicular to the front face and definingopposing sides of the opening; a top wall and a bottom wall extendingfrom the front face along the top and bottom of the opening,respectively, the top and bottom walls being generally perpendicular tothe side guards and extending from the first side guard to the secondside guard, defining a substantially rectangular bounded area on thefront face positioned about the opening; the top wall including an outersurface and a distal edge and the bottom wall including an outer surfaceand a distal edge, and a first raised ramped finger grip positionedproximate the distal edge of the outer surface of the top wall and asecond raised ramped finger grip positioned proximate the distal edge ofthe outer surface of the bottom wall, the raised ramped finger gripscooperating to define opposing finger holds; and at least one fasteneropening through the body for mounting to a switched electrical circuitbreaker with the switch of the circuit breaker extending through theopening into the bounded area.
 6. The finger guard of claim 5, furthercomprising a designation holder extends from the front face adjacent toeither the top wall or the bottom wall outside the bounded area forreceiving indicia.
 7. The finger guard of claim 5, further comprising aknock out positioned in the opening.
 8. The finger guard of claim 5,further comprising a switched electrical circuit breaker mounted to thefinger guard with the switch of the circuit breaker extending into thebounded area.
 9. A finger guard for an electrical circuit breaker, thefinger guard comprising: a body including a front face and a rear face;an opening formed from the front face to rear face, the opening beingapproximately rectangular and having a top and a bottom, the openingsized to receive a switch of an electrical circuit breaker; first andsecond side guards on the front face extending generally perpendicularto the front face and defining opposing sides of the opening; adesignation holder on the front face adjacent to either a top or abottom of the body for receiving indicia; and at least one fasteneropening through the body for mounting to a switched electrical circuitbreaker with the switch of the circuit breaker extending into theopening.
 10. The finger guard of claim 9, further comprising a knock outpositioned in the opening.
 11. The finger guard of claim 9, furthercomprising a switched electrical circuit breaker mounted to the fingerguard with the switch of the circuit breaker extending into the boundedarea.
 12. An electrical power distribution system comprising: a chassisincluding a power input terminal and a power output terminal; thechassis enclosing an electrical bus electrically connected to each ofthe power input and the power output terminals but not providing acontinuous electrical pathway between the power input terminal and thepower output terminal; the electrical bus including a mount for mountinga switched electrical circuit breaker such that the electrical circuitbreaker completes a continuous circuit between the power input and poweroutput terminals; the chassis including an opening allowing access tothe mount for mounting the circuit breaker; and a finger guard mountedin the opening allowing access to the mount for mounting the circuitbreaker, the finger guard comprising: a body including a front face anda rear face; an opening formed from the front face to rear face, theopening sized to receive a switch of an electrical circuit breaker;first and second side guards on the front face extending generallyperpendicular to the front face and defining opposing sides of theopening; a knock-out positioned within the opening, the knock-outremovably attached to the body and substantially blocking the opening;and at least one fastener opening through the body for mounting to aswitched electrical circuit breaker with the switch of the circuitbreaker extending into the opening.
 13. An electrical power distributionsystem comprising: a chassis including a power input terminal and apower output terminal; the chassis enclosing an electrical buselectrically connected to each of the power input and the power outputterminals but not providing a continuous electrical pathway between thepower input terminal and the power output terminal; the electrical busincluding a mount for mounting a switched electrical circuit breakersuch that the electrical circuit breaker completes a continuous circuitbetween the power input and power output terminals; the chassisincluding an opening allowing access to the mount for mounting thecircuit breaker; and a finger guard mounted in the opening allowingaccess to the mount for mounting the circuit breaker, the finger guardcomprising: a body including a front face and a rear face; an openingformed from the front face to rear face, the opening being approximatelyrectangular and having a top and a bottom, the opening sized to receivea switch of an electrical circuit breaker; first and second side guardson the front face extending generally perpendicular to the front faceand defining opposing sides of the opening; a top wall and a bottom wallextending from the front face along the top and bottom of the opening,respectively, the top and bottom walls being generally perpendicular tothe side guards and extending from the first side guard to the secondside guard, defining a substantially rectangular bounded area on thefront face positioned about the opening; the top wall including an outersurface and a distal edge and the bottom wall including an outer surfaceand a distal edge, and a first raised ramped finger grip positionedproximate the distal edge of the outer surface of the top wall and asecond raised ramped finger grip positioned proximate the distal edge ofthe outer surface of the bottom wall, the raised ramped finger gripscooperating to define opposing finger holds; and at least one fasteneropening through the body for mounting to a switched electrical circuitbreaker with the switch of the circuit breaker extending through theopening into the bounded area.
 14. An electrical power distributionsystem comprising: a chassis including a power input terminal and apower output terminal; the chassis enclosing an electrical buselectrically connected to each of the power input and the power outputterminals but not providing a continuous electrical pathway between thepower input terminal and the power output terminal; the electrical busincluding a mount for mounting a switched electrical circuit breakersuch that the electrical circuit breaker completes a continuous circuitbetween the power input and power output terminals; the chassisincluding an opening allowing access to the mount for mounting thecircuit breaker; and a finger guard mounted in the opening allowingaccess to the mount for mounting the circuit breaker, the finger guardcomprising: a body including a front face and a rear face; an openingformed from the front face to rear face, the opening being approximatelyrectangular and having a top and a bottom, the opening sized to receivea switch of an electrical circuit breaker; first and second side guardson the front face extending generally perpendicular to the front faceand defining opposing sides of the opening; a designation holder on thefront face adjacent to either a top or a bottom of the body forreceiving indicia; and at least one fastener opening through the bodyfor mounting to a switched electrical circuit breaker with the switch ofthe circuit breaker extending into the opening.
 15. A method of mountinga circuit breaker to an electrical power distribution chassis comprisingthe steps of: providing an electrical power distribution chassisincluding: a power input terminal, a power output terminal, and anelectrical bus electrically connected to each of the power input and thepower output terminals but not providing a continuous electrical pathwaybetween the power input terminal and the power output terminal; theelectrical bus including a mount for mounting a switched electricalcircuit breaker such that the electrical circuit breaker completes acontinuous circuit between the power input and power output terminals;and the chassis including a front face defining an opening sized toallow access to the means for mounting the electrical circuit breaker;removing a protective guard mounted across the opening in the front faceof the chassis, the protective guard including a front face includingfirst and second side guards and an opening between the side guards,with a removable knock-out substantially covering the opening; removingthe knock-out from the opening of the front face of the protectiveguard; mounting the protective guard to the switched electrical circuitbreaker such that a switch of the circuit breaker protrudes through theopening and between the side guards; and replacing the protective guardacross the opening in the front face of the chassis so that the switchedelectrical circuit breaker engages the mount for the switched electricalcircuit breaker.
 16. A finger guard for an electrical circuit breaker,the finger guard comprising: a body including a switch guard positionedadjacent to a breaker receiving region defined by the body; a removableportion blocking receipt of the breaker in the breaker receiving region;means for mounting the breaker to the body when the removable portion isremoved; and means for mounting the body to a chassis.